The invention relates to a dry material sampling apparatus and more particularly to a crosscut sampler with auger cleanout insertable into a gravity feed flow duct for obtaining a representative sample of a downwardly flowing stream of dry material within the duct.
Granular materials, such as grains, pellets or granules, and powdery materials, such as portland cement, are often conveyed in gravity feed flow ducts. Such dry materials are intially loaded into elevated reservoirs or bins. Ducts are connected to the bottoms of the bins. Gravity may then be utilized as the moving force to disburse the materials into the ducts for sorting, storage elsewhere or usage.
Obtaining a representative sample of a large quantity of dry material is difficult. Dry materials do not have the uniform physical and qualitative consistencies of liquids. Additionally, finer granular materials have a tendency to more readily settle below larger granular materials thereby creating striations within a material of differently sized particles. It is generally accepted that the most representative sample of a dry material may be obtained while the material is being conveyed and flowing within a duct. Such samples may be then analyzed for physical and qualitative characteristics to be used in characterizing the material flowing within the duct at the time of sampling.
In the past, various samplers have attempted to take representative samples from a gravitationally flowing stream of dry materials. U.S. Pat. No. 2,313,715, issued to Andlauer on Mar. 16, 1943 shows a feed volume meter and sampler where the feed is diverted over a corrugated drum, by a swingable gate and into a test box. U.S. Pat. No. 2,738,679, issued to Senkowski on Mar. 20, 1956 discloses a solid sample cutter with an inclined bottom for gravitationally directing the collected sample into a bin. U.S. Pat. No. 2,795,141, issued to Pate on June 11, 1957 reveals a sampler cutter in a sloping material delivery chute which delivers samples into a hopper. Automatic sampler models G/A and G/E, manufactured by Gustafson, Inc. of Dallas, Tex., are crosscut samplers with pelicans insertable in gravity feed flow ducts. The pelicans have inclined bottoms for diverting the samples thereout. The above samplers require sizable vertical spacing or head room for gravity to effectively deliver the material samples therefrom and may not work with both granular powdery materials.
Augers have been used to withdraw sample material from bulk materials as shown in U.S. Pat. No. 3,060,746, issued to Gompper on Oct. 30, 1962, U.S. Pat. No. 3,217,547, issued to Cordell et al. on Nov. 16, 1965 and U.S. Pat. No. 3,383,924, issued to Cordell on May 21, 1968 teach of sampling devices for pressurized conveyors using augers to deliver material samples. These samplers have their augers within tubes having slots for a material sample to enter the tube. Such tubes are stationary or have restricted linear movement. Therefore, they do not give the most accurate sample of a material having any varing characteristics.
There is a need to provide a crosscut sampler that accurately provides representative crosscut samples from a gravity feed flow duct, requires mimimal vertical space and operates with a wide range of granular to powdery materials.